- •Physical foundations of oil fields development and enhanced oil recovery methods
- •Introduction
- •1.2 Pool-reservoir properties.
- •1.3. Heterogeneity and anisotropy of reservoirs
- •2.1. Rock pressure and effective pressure.
- •2.2. Reservoir energy types.
- •2.3. The main sources of reservoir energy.
- •2.4. Operation modes of oil deposits.
- •2.5. Elastic-water drive
- •2.6. Dissolved gas drive
- •2.7. Gas cap drive.
- •2.8. Gravity drive
- •3.1. Productive formation.
- •3.2. The reservoir recovery and oil recovery factor (orf).
- •3.3. The well patterns - development systems of production facilities on natural recovery modes.
- •3.4. Enhanced recovery systems
- •3.5. Field development systems
- •3.5.1. Simultaneous production facilities development
- •3.5.2. Successive development systems.
- •3.6. Oil fields development parameters
- •3.6.1. Technological development parameters
- •3.6.2. Borehole grid. Wells’ density.
- •3.6.3. Krylov’s parameters. Compensation factor. Water cut factor.
- •3.6.4. Oil fields development rates.
- •3.6.5. Development stages of the production facilities (oil fields)
- •3.7. Types of water flooding
- •3.7.1. Edge water flooding.
- •3.7.2. Boundary water flooding
- •3.8. Circle water flooding.
- •3.8.1. Direct line drive systems. Their varieties – block systems.
- •3.8.2. Grid water flooding systems.
- •3.8.3. Selective and Spot water flooding.
- •3.8.4. Barrier water flooding system.
- •4.1. Porous formation models.
- •4.1.1. Deterministic model
- •4.1.2. Stochastic-statistical model.
- •4.2.4. Pollard model.
- •4.2.5. Models use peculiarities of the reservoirs of complex structure.
- •4.3. Water saturation and watering.
- •4.4. Reciprocating and non-reciprocating oil displacement.
- •4.4.1. Reciprocating displacement.
- •4.5. Displacement characteristics.
- •5.2. Project documentation.
- •5.3. Field-geologic characteristic of the deposit.
- •5.4. Rational development system.
- •6.1. Geological peculiarities reservoir structure with high-viscosity oil.
- •6.2. The deposit Russkoye
- •6.3. Katangli deposit.
- •6.4. Canada high-viscosity oil deposits.
- •6.5. The main peculiarities of high-viscosity oil deposits development.
- •7.1. Enhanced oil recovery methods classification.
- •7.2. Production stimulation methods (psm)
- •7.3. Enhanced oil recovery methods (eorm)
- •7.4. The forms of residual oil condition.
- •7.5 The reasons of residual oil condition.
- •7.6. The conditions of effective enhanced oil recovery methods use.
- •7.7. Oil deposits management and enhanced oil recovery methods.
- •8.1. Oil displacement by water solutions of surface-active reagents (sar)
- •8.2. Sar adsorption
- •8.3. Sar (surface-active reagent) composition.
- •8.4. Polymer oil displacement.
- •8.5. Micellar-polymer flooding method.
- •8.6. Conformance change or control (straightening the injectivity profile) (cc)
- •8.7. The choice of the areas and wells for injectability profile enhancement technologies implementation.
- •9.1. Filtration flows’ direction changing.
- •9.2. Forced fluid withdrawal (ffw)
- •9.3. Cyclic water flooding.
- •9.4. Combined non-stationary water flooding.
- •10.1. Oil displacement by carbon dioxide (co2).
- •10.2. Oil displacement by hydrocarbon gas
- •10.3. Water-alternated-gas cyclic injection.
- •11.1. Physical processes, happening during oil displacement by heat-transfer agents.
- •11.2. Oil displacement by hot water and steam.
- •11.3. The method of heat margins.
- •11.4. Combined technologies of enhanced oil recovery of high-viscosity oil deposits.
- •11.5. Thermal-polymer reservoir treatment (tpt)
- •11.6. Cyclic steam treatment of producing wells
- •Disp-lace-ment front
- •Ther-mal front
- •Combustion front
- •Disp-lace-ment front
- •Ther-mal front
- •Injection temperature
- •11.8. Thermal-gas method of treatment.
- •12.1. Formation hydraulic fracturing (fhf)
- •12.2. Well operation with horizontal end.
- •12.3. Acoustic methods.
- •Conclusion.
- •The list of symbols and abbreviations.
- •Content
- •Introduction 3
- •4.1. Porous formation models………………………………………………..38
- •4.1.1. Deterministic model……………………………………………………38
6.5. The main peculiarities of high-viscosity oil deposits development.
The abovementioned review of the geological structure and ways of development of some (not all) fields with high-viscosity oil helps to highlight the main peculiarities. The formations with high-viscosity oil occur at relatively shallow depths, can have extensive gas cap, can be underlaid by stratum water. The rocks are semi consolidated, during the wells operation there can be observed the significant removal of mechanical impurities. Permeability may vary widely from mD to 2-3 D. The geological structure is complex; the formations are split up by the tectonic faults into the blocks. A number of permeable intervals is more than 1.
In this regard, for each operational facility there is its own selected development technology: natural drives, thermal methods. The use of wells with horizontal end both as producing and injection, allows to increase oil production rate. In the Northern areas perennially frozen rocks have significant impact on well production and application of thermal methods. To reduce heat losses it is required to use specially designed wells. During the operation of the producing well the radius of pressure disturbances (depression funnels) is proportional to the cubic root of time; it depends on the flow rate or depression and initial pressure differential (see Annex 1). The initial pressure differential plays an important role in the description, design and modeling of filtration processes of high-viscosity oils. Oil displacement by cold water or coolant also depends on the value of the initial pressure differential.
PART 2. ENHANCED OIL RECOVERY METHODS.
CHAPTER 7. PRODUCTION STIMULATION AND ENHANCED OIL RECOVERY METHODS.
7.1. Enhanced oil recovery methods classification.
During the development of every oil field, the main task is to increase oil production. This task is in the development of new and the development of old depleted fields. Under the depletion is usually understood the reduction of the original reserves of formation energy, accompanied by decreasing of reservoir pressure. The introduction of flooding on the newly developing objects is defined as the primary method of enhanced oil recovery. The events, produced for the extraction of remaining oil reserves from the depleted (old) deposits by flooding, are called the secondary methods of oil recovery.
During the fields development with difficult-to-recover reserves (high-viscosity oil, low permeability, formations’ heterogeneity, interbedded by the impermeable layers and others) it is not effective to implement flooding at a certain stage. Therefore, the actions (technologies) to recover remaining oil reserves from the flooded zones are called the tertiary methods of oil recovery [6].
Recoverable oil and gas reserves can be increased by means of rational wells pattern on the deposit taking into account the geological structure of the formations. Good results are obtained with the regulation of the process of water boundary tightening with the aim of improving the uniformity of various deposit’s parts development. The efficiency of the deposit operation is improved by the bottomhole stimulation of the wells to increase their production rates and oil and gas inflow profiler conformance.
For the long field development practice there were proposed a set of methods and technologies allowing to increase the hydrocarbons withdrawal.
Methods of enhanced oil recovery are based on the application of the reservoir fluids filtration laws; physical, chemical phenomena taking place in the reservoir; on the interaction of solid particles and fluids; on two-way influence of the injected chemicals and oil.
The choice of a certain method of oil recovery and its effectiveness depends on the geological structure of the deposit and its exploration, pool-reservoir properties, technologies, applied from the beginning of the development, the oil withdrawal rate and fluid injection. Each developing production facility is considered to be chosen the individual methods with consideration of the peculiarities of geological structure and pool-reservoir properties of the developing deposits.
Enhanced oil recovery methods are divided into oil production stimulation methods (PS methods) and enhanced oil recovery methods (EOR methods)